A massive Garda investigation been launched after the force received credible intelligence that criminals were plotting to have two officers shot.

The alleged targets are officers investigating a major criminal feud in Drogheda, Co Louth.

The threats were made in a phone call to a prison, where a number of the feuding gangsters are located having been charged over related incidents.

The suspects at the centre of the threats are members of the same gang which was involved in the failed murder attempt on Owen Maguire in July, which inflamed the feud.

They were also involved in a petrol bomb attack on a house at 12.15am yesterday.

"All gardaí in Drogheda have been strongly advised to be extra-vigilant in relation to this credible threat from one of the feuding gangs," a senior source said last night.

As gardaí scrambled to deal with the death threats, an innocent mother and her four children were lucky to escape with their lives after a petrol bomb was thrown into their house in Drogheda in the early hours of yesterday.

The family fled their home in terror as the bomb set fire to the living room, filling the house with smoke.

Gardaí believe the house, in Laurence's Park, was targeted in the feud between rival drug factions in the town which has escalated in recent months after the shooting of Maguire .

It's understood the family were not involved in the feud, but may have been targeted because one member of the family is friends with a man aligned to the Maguire faction.

Gardaí sealed off the terrace house for a forensic examination by the technical bureau.

Several houses have been firebombed in the town in recent weeks as the feud spirals out of control.

Tensions are now so high Justice Minister Charlie Flanagan visited Drogheda and met with senior gardaí and officers who regularly patrol the streets trying to keep a lid on the violence.

He was also brought to the Moneymore estate where he saw first hand the damage caused by the fighting factions.

The feud was discussed in the Dáil by Fianna Fáil TD Declan Breathnach who said: "This morning the Minister for Justice and Equality, Deputy Flanagan, is visiting the garda station in Drogheda.

"He is meeting Chief Superintendent Christy Mangan to discuss the excellent work being done by gardaí in their efforts to deal with a powder keg situation that is ongoing in Drogheda, a drug-related feud.

"Since July, gardaí in Drogheda have been dealing with shootings, kidnappings, intimidation, petrol bombings and incendiary devices while today the lives of two named gardaí were threatened.

"The situation is getting out of control, despite the best efforts of An Garda Síochána.

"When will An Garda Síochána be in a position to deal with these types of pressure cooker situations which, as I have said previously, are happening to a lesser degree in towns and villages all across this country?"

Tánaiste Simon Coveney answered: "The examples which the deputy has provided are why the Minister of Justice and Equality is speaking to senior gardaí to ensure they have the resources and powers they need to be able to act."